1. Field of the Invention
This invention relates to a main-shaft malfunction-state detector in an air bearing type machine tool, using for detecting an abnormal contact of a main shaft in a machine tool for a cutting process of a relatively heavy load in which the main shaft is supported in an air static-pressure bearing, and so on.
2. Description of the Related Art
Conventionally, a machine tool is used for, for example, cutting various metallic materials.
The machine tool has a cutting tool attached at an end of a main shaft rotatably supported, in which the tool is rotated by rotatably driving the main shaft with a shaft driving motor, thereby performing a cutting process for a work piece.